I'm confused by your confusion about the confusion... LOL!!!
We all (or at least 99% of us) know that there is a closed caption button that shows up when you press the up button on the Roku remote. We have all gone there 1000 times. Our problem is that it doesn't work. Occasionally I will go into Peacock and the CC will be on but 9 out of 10 times it isn't. When I say it isn't on, I mean that it is set to on but the CC isn't working. This is NOT a case of just turning it on. This isn't mass hysteria that for several years now we are imagining that this isn't working. We are also not idiots that can't figure out how to turn on CC for several years. To me, if I saw this many people with the same problem and even some workarounds, I would assume there really is a problem that has been irritating people for several years. I figured out the workaround a long time ago so I didn't find this thread until recently when I just couldn't understand why this hasn't been fixed after several years. Nobody at Roku takes it seriously. They always assume all of these people are idiots who can figure out how to turn on CC. They never take the time to read all of the posts where users take the time to try and help. I can only assume that not everybody experiences this problem or there wouldn't be so many posts telling us to push the up button on the remote and then navigate to the CC menu.
The workaround: If you have read through this post you will have already seen it but here it is again... exit Peakcock and restart it. I have found this doesn't always work (but I haven't tested it in over a year) so when I exit Peacock I start up another app and load a show/movie. I then exit that app and restart Peakcock and the CC are magically working when I load the show/movie I want to watch.
I hope this helps with your confusion! If you don't work for Roku, my sarcasm wasn't directed at you. If you do work for Roku.... well, I think you get my point.
PS... I love Roku!!!